Party wall surveying is the process of managing the legal duties that arise when building work affects a shared wall, boundary or nearby structure. Under the Party Wall etc. Act 1996, a person planning certain works must notify affected neighbours, and where there is disagreement, an impartial surveyor (or surveyors) produces a binding document called a party wall award. The aim is to let work proceed while protecting both parties from damage and dispute.
When does the Party Wall Act apply?
The Act applies in England and Wales to specific categories of work, not to every building project. It is triggered by the type of work and its proximity to a neighbour's property, not by whether the neighbour objects. If the work falls within scope, notice is required even when relations are good.
The three main situations covered are:
- Work to an existing party wall or party structure — for example cutting into it to insert a beam, removing a chimney breast, raising the wall, or rebuilding part of it. A party wall here usually means a wall shared between two properties, or one that sits astride the boundary.
- Building a new wall at or astride the boundary line — including a new wall built up to the boundary of two owners' land.
- Excavating near a neighbouring building — generally within three metres and to a lower depth than the neighbour's foundations, or within six metres where deep foundations are involved. This often catches basement projects and many rear extensions.
Common works that fall under the Act include loft conversions involving the party wall, single and double-storey extensions, basement digs, and underpinning. Routine internal decoration or fixing shelves does not. If there is any doubt about whether a project is notifiable, a surveyor can advise on the technical thresholds before work is committed.
Serving notice on an adjoining owner
Party wall surveying is the process of managing the legal duties that arise when building work affects a shared wall, boundary or nearby structure.
The person carrying out the work — the building owner in the language of the Act — must serve written notice on each adjoining owner before work begins. An adjoining owner is anyone with an interest in the neighbouring property, which can include both a freeholder and a leaseholder. All relevant owners need to be served.
The notice period depends on the work. Notice for excavation or for a new wall at the boundary must be served at least one month before work starts. Notice concerning an existing party wall must be served at least two months in advance. The notice should describe the proposed work, the address, the building owner's details, and the date of service, and for excavation it should include plans showing the depth and position of the work.
Once served, the adjoining owner has fourteen days to respond. There are three possible outcomes:
- Consent — the neighbour agrees in writing, and no award is needed, though a record of the wall's condition is still sensible.
- Dissent with an agreed surveyor — both owners appoint a single surveyor to act impartially for them both.
- Dissent with separate surveyors — each owner appoints their own surveyor, and the two surveyors together select a third surveyor to resolve any point on which they disagree.
If the adjoining owner does not respond within fourteen days, a dispute is deemed to have arisen and the surveyor process begins. Silence is not consent. The surveyor's role from this point is statutory and impartial — even a surveyor appointed by one owner must act fairly to both, not as an advocate.
What goes into a party wall award
A party wall award is the legal document that settles how notifiable work may proceed. It is prepared and signed by the appointed surveyor or surveyors and is binding on both owners, subject to a limited right of appeal to the county court within fourteen days of service. The award is sometimes called a party wall agreement, though it is an award made by surveyors rather than a contract between neighbours.
A typical award sets out:
- The work that is authorised, described clearly enough to define its limits.
- The method and timing of the work, including working hours and access arrangements where the building owner needs to enter the neighbour's land.
- A schedule of condition recording the state of the adjoining property before work starts.
- How any damage caused by the work will be made good or compensated.
- Which party bears the surveyors' fees — usually the building owner, as it is their project, though the award can apportion costs differently.
- Provisions for inspection during the work and resolution of disputes through the third surveyor if needed.
The award does not give permission for the work in a planning or building-control sense; those consents are separate. It governs the party wall aspects only. Once made and served, both owners should keep a copy, as it protects each of them if a disagreement arises later.
The schedule of condition explained
A schedule of condition is a detailed factual record of the state of the adjoining property before notifiable work begins. It is usually compiled by the surveyor and forms part of, or is attached to, the award. Its purpose is to provide an agreed baseline, so that any later claim of damage can be measured against a clear starting point.
The schedule typically describes the relevant rooms and external elevations near the work, noting existing cracks, settlement, damp, decorative defects and any other visible features. Written descriptions are normally supported by dated photographs. The more thorough the record, the fewer arguments tend to arise about whether a defect is new or pre-existing.
Without a schedule of condition, disputes over damage can become difficult to resolve, because there is no impartial evidence of how the property looked beforehand. For this reason the document is often regarded as the most practically useful part of the process, even where neighbours are on good terms and have consented. Where work later causes genuine damage, the schedule helps establish what is owed and keeps the matter from escalating.
Last reviewed: June 2026